Question

( x² + 2x + x² - 4): (x + 2)

Answer 1

x²+2x+x²-4=x(x+2)+(x-2)(x+2)=(x+2)(2x-2)

=>(x+2)(2x-2):(x+2)=2x-2

Answer 2

( x² + 2x + x² - 4): (x + 2)

= [(x² + 2x) + (x² - 4)] : (x + 2)

= [x(x + 2) + (x - 2)(x + 2)] : (x + 2)

= (x + 2)(x + x - 2) : (x + 2)

= (x + 2)(2x - 2) : (x + 2)

= 2x - 2

= 2(x - 1)

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